The 74F14 is a six-inverter Schmitt trigger IC produced by Philips. It accepts standard TTL input signals and provides standard TTL output levels. It can transform slowly changing input signals into sharply defined, jitter-free output signals. In addition, it has greater noise margin than conventional inverters. Each circuit contains a Schmitt trigger followed by a Darlington level shifter and a phase splitter driving a TTL totem-pole output. The Schmitt trigger uses positive feedback to effectively speed-up slow input transitions, and provide different input threshold voltages for positive-going and negative-going input threshold (typically 800mV) is determined internally by resistor ratios and is insensitive to temperature and supply voltage variations.